This application addresses broad Challenge Area (06) Enabling Technologies, and Specific High-Priority Topic Area 06-OD(OBSSR)-101* "Using new technologies to improve or measure adherence". The chronic diseases that constitute the major killers of American adults, among them cardiovascular disease, cancer, and other diseases of aging, are inextricably linked with key health behaviors. These include regular physical activity and, more recently, sedentary behaviors such as prolonged television viewing that are associated with obesity, type-2 diabetes, and other hazardous health conditions. Unfortunately, regular adherence to healthful behavioral regimens remains poor across the majority of Americans. Recent advances in communication technologies such as 'smart phones'offer a potentially transformative platform for addressing common barriers to adherence through delivering convenient, sustainable, and contextually meaningful adherence strategies. The major objectives of this research are to develop and test theoretically based behavioral interventions, delivered via state-of-the-art mobile phone technology and aimed at increasing moderate-intensity physical activity (PA) and decreasing TV viewing among adults who could particularly benefit from such programs. During Year 01, participatory qualitative and quantitative research methods will be applied based on preliminary work to develop and formatively test the two mobile phone programs in the target population (i.e., adults ages 25 years and older who have low physical activity levels, watch greater than 14 hours of TV/week, and are overweight or obese). In Year 02, an experimental 4-month pilot study will be conducted to test the feasibility and preliminary efficacy of the two mobile phone programs. Up to 90 adults meeting eligibility criteria will be randomized to the mobile phone-PA, mobile phone-TV, or a mobile phone Control program. In light of the high prevalence of inactivity, overweight, and prolonged TV viewing among lower-income and midlife and older adults, study recruitment activities will particularly target those groups. Daily physical activity and TV viewing will be assessed through a combination of automated methods built or programmed into the phones (e.g., accelerometry, location 'aware'methods) along with user-provided information. Process variables (e.g., program satisfaction) will be assessed. Change in intermediate health outcomes (e.g., body weight, resting blood pressure and heart rate) and other relevant health behaviors (TV-related eating) will be assessed. The effect size, process, and outcomes information generated by this research will inform a subsequent larger trial evaluating the longer-term impacts and cost-effectiveness of the two mobile phone programs in promoting sustained behavioral adherence. The project will yield programs that, once evaluated in a larger trial, can be readily disseminated across the U.S. population at potentially low cost. The potential public health impacts are thus substantial. The project also will create new jobs, both within the context of the grant as well as in the private sector, if the types of technology innovations the project is aiming to create come to fruition. (According to the California Biomedical Industry, for every one employee of a biotechnology organization, another three to five will be employed in firms that service that industry.) Among the innovations of the proposed research are the focus on a state-of-the-art mobile technology platform that represents a convenient and increasingly available and acceptable means of reaching a substantial proportion of U.S. adults;intervention-specific applications of mobile phone technology that extend beyond the areas of assessment and monitoring where current research efforts have been aimed primarily;targeting of two different, highly prevalent health behaviors linked with chronic disease risk;and development, testing, and refinement of what, to our knowledge, will be the first intervention and monitoring technology aimed specifically at reducing TV viewing time among adults. In addition, we will utilize our collaborative relationship with the integrated consumer experience group at a large U.S. health insurance company (Humana) to explore potential translation and dissemination activities as well as subsequent funding mechanisms in furthering the technology evaluation and transfer activities stemming from the proposed research. Despite the recognized health benefits of increasing weekly levels of physical activity and reducing sedentary activities associated with obesity and other health problems, most American adults find it challenging to do so on an ongoing basis. This research aims to develop and evaluate effective, convenient, and easy to use behavioral programs, delivered by state-of-the-art mobile phone technologies, for increasing walking and decreasing prolonged television viewing. Such mobile phone-based programs represent an emerging, potentially cost-effective means for reaching a substantial proportion of Americans in a convenient, contextually meaningful, and ongoing fashion.